1. Field of the Invention
This invention pertains to a jig which is designed to hold a blank in a fixed position during machining operations such as lapping. More particularly, this invention pertains to a jig which will automatically feed a single stylus blank from a stack of stylus blanks, hold the single blank in a fixed position during machining, eject a machined stylus, and hold a subsequent stylus blank in a fixed position for a subsequent machining operation.
2. Description of the Prior Art
It is known to use a stylus such as that disclosed in U.S. Pat. No. 4,162,510 issued to E. O. Keizer on July 24, 1979 and assigned to RCA Corporation to read signals from grooves which are cut into an information record such as a plastic disc. A blank made of a relatively hard material (such as diamond) is used to manufacture the stylus. The blank is lapped along certain crystal planes to take advantage of properties exhibited by the surfaces along these planes. It is necessary to hold the blank in a fixed position during lapping in order to insure lapping accuracy.
In the commonly-owned patent applications of Ziegel, Ser. No. 118,214, filed Feb. 4, 1980 and entitled "WORK HOLDER", and of Manson, Ser. No. 172,758, filed July 28, 1980 and entitled "STONE-POSITIONING APPARATUS AND METHOD", devices are disclosed which can hold an individual stylus blank in a fixed position during lapping. In both of these devices, individual stylus blanks are manually introduced into a jig and are manually withdrawn therefrom. Since the stylus blanks are relatively small and each one must be handled manually, manufacture of styli from stylus blanks using these devices is a labor-intensive and time-consuming process.
It would therefore be advantageous to provide a jig which would be able to store a plurality of stylus blanks, hold individual stylus blanks in a fixed position for accurate lapping, and enable a finished stylus to be ejected and replaced by another stylus blank automatically, without requiring manual handling of individual stylus blanks.